Interposable heat sink for adjacent memory modules

ABSTRACT

A heat sink device for conventional memory modules, such as DIMMs, that is configured to be positioned between adjacent memory modules mounted in substantially parallel connectors on a printed circuit board. Each heat sink device includes thermally conductive first and second members configured to thermally couple with electronic components of a conventional memory module. The first and second members may be resiliently biased away from one another so that the resilient bias causes the members to abut respective electronic components when placed between adjacent memory modules. A separate wedge, or a lever-mounted wedge, may be provided for insertion between the members to urge them away from one another and into abutting relationship with electronic components on facing surfaces of the adjacent memory modules. When abutting opposing electronic components, a single heat sink device facilitates heat dissipation from both of the adjacent memory modules.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.11/093,445, filed Mar. 30, 2005, now U.S. Pat. No. 7,289,331 the entiredisclosure of which is hereby incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to a heat sink device configuredto dissipate heat from electronic components of a conventional memorymodule, such as a SIMM or DIMM.

DISCUSSION OF RELATED ART

Conventional memory modules include multiple individual memory chipsarranged on a printed circuit board that is configured to mate with aconventional connector of a motherboard of a PC, etc. Such conventionalmemory modules conform to industry standards of size, configuration etc.Exemplary memory modules include SIMMs and DIMMs.

Recent increases in the integration density of memory integratedcircuits on memory modules, and the development of newer memory ICs,such as DDR2 ICs, have resulted in memory modules that run “hotter.”Further, many vendors of conventional memory modules have lowered theDIMM junction temperature specifications while power requirements haveincreased. Further still, newer CPUs are tending to run hotter, and thememory modules are receiving preheated air from the exhaust of the CPU'sheat sink, making it more difficult to cool memory modules in aconventional manner.

An exemplary conventional module is shown in FIGS. 1 and 2, which arediagrammatic plan and side views of the memory module. As shown in FIGS.1 and 2, the memory module is generally designated with reference number10, and includes a number of packaged memory ICs 12 and a plurality ofchip-type capacitors 14 mounted on each face of a printed circuit board16. The printed circuit board 16 has an array of contacts 18 providedalong a long-side edge of each face of the printed circuit board 16 forelectrical connection with an appropriate mating socket of amotherboard, etc.

As seen from FIGS. 1 and 2, the semiconductor memory ICs 12 and thechip-type capacitors 14 are mounted on each face of the printed circuitboard 16 (in a DIMM), and the memory module 10 is inserted into aconnector slot (not shown) within a system such as a personal computeror other information processing system. Therefore, heat generated in thememory ICs 12 is radiated from only the surface of the memory ICs 12.

SUMMARY OF THE INVENTION

The present invention provides a heat sink device for conventionalmemory modules, such as DIMMs, that is configured to be interposedbetween adjacent memory modules, and to dissipate heat from separate,adjacent memory modules.

The heat sink device includes thermally conductive first and secondmembers. Each member has a respective surface configured to thermallycouple with electronic components of a conventional memory module.

In one embodiment, the first and second members are resiliently biasedaway from one another. When placed between adjacent memory modulesmounted in substantially parallel connectors on a printed circuit board,the resilient bias causes the first and second members of the heat sinkdevice to abut respective electronic components on opposed surfaces ofthe adjacent memory modules.

In another embodiment, a separate wedge member, or a lever-mounted wedgemember is driven between the first and second members to urge them awayfrom one another and into abutting relationship electronic components onopposed surfaces of the adjacent memory modules.

When abutting opposing electronic components, a single heat sink devicefacilitates heat dissipation from both of the adjacent memory modules.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described by way of example withreference to the following drawings in which:

FIGS. 1 and 2 are diagrammatic plan and side views, respectively, of anexemplary memory module of the prior art;

FIG. 3 is a diagrammatic side view of a plurality of heat sink devicesaccording to a first embodiment of the present invention, showninterposed among an array of exemplary memory modules of FIGS. 1 and 2;

FIG. 4 is a diagrammatic top view of the heat sink devices and memorymodules of FIG. 3;

FIG. 5 is an alternative exemplary embodiment of a heat sink device inaccordance with the present invention;

FIG. 6 is a diagrammatic side view of the exemplary heat sink device ofFIG. 5, shown interposed between adjacent memory modules;

FIG. 7 is a diagrammatic side view of another alternative exemplaryembodiment of a heat sink device in accordance with the presentinvention; and

FIG. 8 is a diagrammatic side view of the heat sink of FIG. 7, shownwith a lever-style wedge mechanism.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides a heat sink device configured todissipate heat from electronic components of a conventional memorymodule, such as a DIMM. Unlike a conventional heat sink device that isattached directly to a memory in an “on-the-module” design, the presentinvention provides heat sink devices configured to be interposed betweenadjacent memory modules in a “between-the-modules” design.

Referring now to FIGS. 3 and 4, heat sink devices 20 in accordance withone embodiment of the present invention are shown. It will beappreciated from FIGS. 3 and 4 that the heat sink devices 20 areconfigured to dissipate heat from conventional memory modules, such asDIMMs, while further, the inventive heat sink devices 20 can beinstalled and used without any need for any modification to theconventional memory module, and without the need for any tools. Furtherstill, the heat sink devices are configured to be fitted to conventionalmemory modules after such modules are mounted as conventional connectorsof a printer circuit board, such connectors being relied upon to providepositional stability used in accordance with the present invention.Accordingly, the heat sink devices 20 are shown in a conventionalenvironment, namely, among conventional memory modules 10 a, 10 b, 10 c,10 d (DIMMs in FIGS. 3 and 4) that are supported in substantiallyparallel positions on adjacent connectors 52 of a printed circuit board50, such as a motherboard of a PC or other information processingsystem.

Referring again to FIGS. 3 and 4, the heat sink devices 20 include firstand second members 22, 24. Each member 22, 24 is constructed of asuitable thermally conductive material, such as copper or aluminum, andis thus suitable for use as a heat spreader or heat sink to facilitateheat dissipation and corresponding connective cooling of memory modules.

Each of the first and second members 22, 24, has a respective firstsurface 22 a, 24 a configured to thermally couple with electroniccomponents of conventional memory modules e.g. memory ICs 12. The firstsurface 22 a of the first member 22 will couple with electroniccomponents of a first memory module (e.g. 10 b) and the second surface24 a of the second member 24 will couple with electronic components of asecond memory module (e.g. 10 c), as discussed in greater detail below.

In this embodiment of the present invention, the first and secondmembers 22, 24 are resiliently biased away from one another. This biascauses the first and second members 22, 24 to abut respective electroniccomponents 12 a, 12 b on the opposed surfaces 16 a, 16 b of adjacentmemory modules 10 b, 10 c. In other words, this bias facilitates wedgingof the heat sink device 20 between adjacent memory modules. Accordingly,a single heat sink device 20 is used to dissipate heat from two adjacentmemory modules.

In FIGS. 3 and 4, the first and second members 22, 24 are biased by aspring member 36 joined to one of the first and second members 22, 24.In this exemplary embodiment, the first member 22 includes a pluralityof elongated sockets 30 a, 30 b, 30 c, 30 d. Further, the second member24 includes a plurality of complementary elongated pins 32 a, 32 b, 32c, 32 d, each riding in a respective socket. Alternatively, the firstmember 22 includes the pins and the second member 24 includes thesockets. In another alternative embodiment, each member includes atleast one pin and at least one socket, and the other member includescomplementary pins and sockets.

Preferably, each spring members 36 a, 36 b, 36 c, 36 d includes a coilspring, which optionally is generally conical in shape. Each springmember is preferably positioned within a respective socket, andoptionally is joined to the pin or the socket, or both the pin and thesocket. By way of example, each pin may include a peripheral groove forreceiving and retaining a portion of the coil spring. Alternatively, thepin may be integrally formed with or mechanically joined to the pin orsocket.

Preferably, each member 22, 24 includes a respective set of conductivefins 42, 44, to enhance the cooling effect provided by the heat sinkdevice 20. The fins 42, 44 are preferably arranged on each member suchthat the fins 42 of the first member 22 are positioned to interleavewith the fins 44 of the second member 24, as shown in FIGS. 3 and 4.This type of arrangement is preferred to allow the fins to be relativelylong. i.e., longer than half of the distance between the members 22, 24.However, any suitable configuration of fins may be employed.

Optionally, the exemplary device 20 may also be used to cool a memorymodule on a periphery of an array of memory modules, i.e., where thereis no second memory module between which the device 20 may beinterposed. Such a memory module is shown at A in FIGS. 3 and 4. To usethe device in this manner, the motherboard 50 or housing (not shown) ofan information processing system, etc. may optionally be provided with abrace 60, such that the device 20 may be interposed between a memorymodule 10 d and the brace 60, with the brace 60 acting as a substitutefor an adjacent memory module.

In use, this embodiment of the heat sink device 20 is first squeezed tocompress the spring member(s) move the first and second members 22, 24toward one another. In this compressed state, the heat sink device 28 isreadily manually positioned between adjacent memory modules 10 b, 10 c(or between a memory module 10 d and a brace 60). Once positionedbetween adjacent memory modules 10 b, 10 c, the squeezing force isreleased to allow the spring member(s) 36 a, 36 b, 36 c and 36 d toresile. The resiling of the spring members causes the first and secondmembers 22, 24 to move outwardly, away from one another, and intoabutting relationship with the electronic components 12 of the adjacentmemory modules 10 b, 10 c. This abutting relationship provides thermalcoupling of the electronic components 12 with the heat sink device 20 tofacilitate convective cooling of the memory modules 10 a, 10 b.Accordingly, the heat sink device 20 may be installed and retained in atool free manner, without the need to modify a conventional memorymodule.

In the alternative embodiment of FIG. 5, the device 20 further includesa retention module 70. In one embodiment, the retention module 70 ismade of a highly thermally conductive material such as copper oraluminum, i.e. a material similar to that of the members 22, 24. In analternative embodiment, the retention module 70 is made of a materialhaving a thermal conductivity less than that of the first and secondmembers. Preferably, the retention module 70 is formed as a unitarybody, e.g. by stamping and crimping sheet metal stock, by forming aninjection molded body, etc.

The retention module 70 includes a pair of opposing legs 72, 74 to whichthe first and second members 22, 24 are mounted, e.g. by heat staking,mechanical fasteners, etc. Preferably, each of the legs 72, 74 defines aplurality of openings 76 for admitting passage of air adjacent the firstand second members to facilitate convective cooling.

FIG. 6 is a diagrammatic side view of the exemplary heat sink device 20of FIG. 5, shown interposed between adjacent memory modules 10 a, 10 b.In this embodiment, the legs 72, 74 are resiliently deflectable towardone another to resiliently bias the first and second members 22, 24 awayfrom one another. More specifically, the retention module 70 isconfigured so that in its relaxed state it is not readily insertablebetween adjacent memory modules 10 a, 10 b. Instead, the legs 72, 74 aresqueezed together (e.g. manually) during insertion of the head sinkdevice 20 between adjacent memory modules 10 a, 10 b.

In use, this embodiment of the heat sink device 20 is first squeezed toresiliently deflect the legs 72, 74 inwardly and to move the first andsecond members 22, 24 toward one another. In this compressed state, theheat sink device 20 is readily manually positioned between adjacentmemory modules 10 a, 10 b. Once positioned between adjacent memorymodules 10 a, 10 b, the legs 72, 74 are permitted to resile. Theresiling of the legs 72, 74 causes the first and second members 22, 24to move outwardly, away from one another, and into abutting relationshipwith the electronic components 12 a, 12 b of the adjacent memory modules10 a, 10 b. This resiling effectively wedges the heat sink device 20between the adjacent memory modules, the heat sink being capable ofretained in place by friction alone. This abutting relationship providesthermal coupling of the electronic components 12 with the heat sinkdevice 20 to facilitate convective cooling of the memory modules 10 a,10 b. Accordingly, the heat sink device 20 may be installed and retainedin a tool free manner, without the need to modify a conventional memorymodule.

FIG. 7 is a side view of another alternative exemplary embodiment of aheat sink device in accordance with the present invention. Thisembodiment is similar to that of FIG. 6. However, in this embodiment,the retention module 70 is not configured to have, or to rely upon,outward resilient biasing of the module's legs 72, 74. Instead, theretention module 70 is configured to be readily insertable in itsrelaxed state between adjacent memory modules 10 a, 10 b, as shown inFIG. 7.

Accordingly, in the embodiment of FIG. 7, no tools and no squeezingforce is required. In this embodiment, a wedge member 80 (FIG. 7) isselectively positionable between the first and second members 22, 24 tourge the first and second members away from one another and intoabutting relationship with respective electronic components 12 a, 12 bof opposed/facing surfaces of adjacent memory modules 10 a, 10 b.

In this exemplary embodiment, the wedge member 80 is provided as adiscrete member that is positionable between the opposing legs 72, 74 tourge the first and second members 22, 24 away from one another, e.g. bymanually pressing the wedge 80 between the legs 72, 74.

In use, this embodiment of the retention module 70 is simply manuallypositioned between adjacent memory modules 10 a, 10 b. A wedge member 80is then manually pressed between the legs 72, 74 to urge the first andsecond members 22, 24 away from one another and into abuttingrelationship with the electronic components 12 a, 12 b of the adjacentmemory modules 10 a, 10 b. This provides thermal coupling of theelectronic components 12 a, 12 b with the heat sink device 20 tofacilitate convective cooling of the memory modules 10 a, 10 b.

Accordingly, the heat sink device 20 may be installed and retained in atool free manner, without the need to modify a conventional memorymodule.

In the alternative embodiment shown in FIG. 8, the printed circuit board50 is specially configured in accordance with the present invention toinclude a lever 90 pivotably mounted to the printed circuit board 50 onsupports 92. The lever 90 supports the wedge member(s) 80 and isselectively pivotable between a first position, in which the wedgemember 80 will not interfere with the device 20 during its insertionbetween adjacent memory modules 10 a, 10 b, and a second position, inwhich the wedge member 80 is interposed between the opposing legs 72, 74to urge the first and second members 22, 24 away from one another andinto contact with adjacent memory modules.

In use, this embodiment of the retention module 70 is simply manuallypositioned between adjacent memory modules 10 a, 10 b with the lever 90in the first position. The lever 90 is then pivoted from the firstposition to the second position to drive the wedge(s) between the legs72, 74 of the retention module 70. The interposition of the wedge(s)urges the first and second members 22, 24 into abutting relationshipwith the electronic components 12 a, 12 b of the adjacent memory modules10 a, 10 b, and thereby provides thermal coupling of the electroniccomponents with the heat sink device 20 to facilitate convective coolingof the memory modules 10 a, 10 b.

While there has been described herein the principles of the invention,it is to be understood by those skilled in the art that this descriptionis made only by way of example and not as a limitation to the scope ofthe invention. Accordingly, it is intended by the appended claims, tocover all modifications of the invention which fall within the truespirit and scope of the invention.

1. A device for dissipating heat generated by electronic components onopposed surfaces of a pair of adjacent memory modules supported insubstantially parallel positions on adjacent connectors of a printedcircuit board, the device comprising: a thermally conductive firstmember having a respective first surface configured to thermally couplewith electronic components of a first of the pair of adjacent memorymodules; and a thermally conductive second member having a respectivefirst surface configured to thermally couple with electronic componentsof a second of the pair of adjacent memory modules; said first andsecond members being resiliently biased away from one another to causesaid first and second members to abut respective electronic componentson the opposed surfaces of the adjacent memory modules; and a retentionmodule formed as a unitary body and having a pair of opposing legs, saidlegs being resiliently deflectable toward one another to resilientlybias said first and second members away from one another, each one ofsaid first and second members being mounted to a respective one of saidpair of opposing legs.
 2. The device of claim 1, wherein said retentionmodule is formed of crimped sheet metal.
 3. The device of claim 1,wherein said retention module has a thermal conductivity less than thatof the first and second members.
 4. A device for dissipating heatgenerated by electronic components on opposed surfaces of a pair ofadjacent memory modules supported in substantially parallel positions onadjacent connectors of a printed circuit board, the device comprising; athermally conductive first member having a respective first surfaceconfigured to thermally couple with electronic components of a first ofthe pair of adjacent memory modules; a thermally conductive secondmember having a respective first surface configured to thermally couplewith electronic components of a second of the pair of adjacent memorymodules; said first and second members being spaced to permit insertionbetween said adjacent memory modules; and a wedge member selectivelypositionable between a first position in which said wedge member urgessaid first and second members away from one another and into abuttingrelationship with respective electronic components of said opposedsurfaces of said adjacent memory modules, and a second position in whichwedge member does not urge said first and second members away from oneanother and into said abutting relationship.
 5. The device of claim 4,further comprising; a retention module having a pair of opposing legs,each one of said first and second members being mounted to a respectiveone of said pair of opposing legs.
 6. The device of claim 5, whereineach of said pair of opposing legs defines a plurality of openings foradmitting passage of air adjacent said first and second members.
 7. Thedevice of claim 5, wherein said retention module is formed as a unitarybody.
 8. The device of claim 5, wherein said retention module has athermal conductivity less than that of the first and second members. 9.The device of claim 7, wherein said retention module is formed ofcrimped sheet metal.
 10. An information processing system comprising; aprinted circuit board supporting a pair of connectors in substantiallyparallel positions adjacent one another, each of said connectors beingcapable of receiving a respective memory module; a pair of memorymodules, each of said plurality of memory modules being mounted in arespective one of said pair of connectors, one of said plurality ofmemory modules supporting electronic components on a first side thereof,another of said plurality of memory modules supporting electroniccomponents on a second side thereof, said first side facing said secondside; a device for dissipating heat generated by said electroniccomponents, said device comprising: a thermally conductive first memberabutting said electronic components of said first side in thermalcoupling therewith; and a thermally conductive second member abuttingsaid electronic components of said second side in thermal couplingtherewith; wherein said first and second members are resilientlydeflected away from one another and into abutting relationship with saidelectronic components by a wedge member interposed therebetween, saidwedge member being supported on said printed circuit board to pivotbetween a first position, in which said wedge member will not interferewith the device during its insertion between memory modules, and asecond position, in which said wedge member deflects said first andsecond members away from one another, said deflection maintaining saidfirst and second members in abutting relationship with said electroniccomponents of said first and second sides of said memory modules. 11.The information processing system of claim 10, further comprising; alever pivotably mounted to said printed circuit board, said leversupporting said wedge member, said lever being selectively pivotablebetween a first position, in which said wedge member will not interferewith said device during insertion of said device between adjacent memorymodules, and a second position, in which said wedge member is interposedbetween said opposing-legs first and second members to urge said firstand second members away from one another.
 12. An information processingsystem comprising; a printed circuit board supporting a pair ofconnectors in substantially parallel positions adjacent one another,each of said connectors being capable of receiving a respective memorymodule; a pair of memory modules, each of said plurality of memorymodules being mounted in a respective one of said pair of connectors,one of said plurality of memory modules supporting electronic componentson a first side thereof, another of said plurality of memory modulessupporting electronic components on a second side thereof, said firstside facing said second side; a device for dissipating heat generated bysaid electronic components, said device comprising: a thermallyconductive first member abutting said electronic components of saidfirst side in thermal coupling therewith; a thermally conductive secondmember abutting said electronic components of said second side inthermal coupling therewith; and a retention module formed as a unitarybody and having a pair of opposing legs, each one of said first andsecond members being mounted to a respective one of said pair ofopposing legs, said wedge member comprising a discrete member interposedbetween said opposing legs to urge said first and second members awayfrom one another.
 13. The device of claim 12, wherein said retentionmodule is formed of crimped sheet metal.